Space-Time Point Pattern Analysis of Flavescence Dorée Epidemic in a Grapevine Field: Disease Progression and Recovery

Maggi, Federico; Bosco, Domenico; Galetto, Luciana; Palmano, Sabrina; Marzachı̀, Cristina

doi:10.3389/fpls.2016.01987

Cited by 24 publications

(35 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the other sites, FDp genetic diversity was consistent with the hypothesis of "primary infection" by incoming vectors from outside the vineyard. This hypothesis is further supported by the "edge" effect recorded for FDp-infected grapevines (17)(18)(19). Primary infections are likely to occur late in the season, when cultivated grapevines are no longer protected by insecticides, due to the need for respecting a safety period before grape harvest (20).…”

Section: Discussionmentioning

confidence: 88%

Genetic Diversity of Flavescence Dorée Phytoplasmas at the Vineyard Scale

Rossi

Pegoraro

Ripamonti

et al. 2019

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

To study the role of wild areas around the vineyards in the epidemiology of flavescence dorée (FD) and track the origin of new foci, two phytoplasma genetic markers, dnaK and malG, were developed for FD phytoplasma (FDp) characterization. The two genes and the vmpA locus were used to genetically characterize FDp populations at seven agroecosystems of a wine-growing Italian region. Vitis vinifera, “gone-wild” V. vinifera and rootstocks, Clematis spp., and Scaphoideus titanus adults were sampled within and outside the vineyards. A range of genotypes infecting the different hosts of the FDp epidemiological cycle was found. Type FD-C isolates were fairly homogeneous compared to type FD-D ones. Most of the FD-D variability was correlated with the malG sequence, and a duplication of this locus was demonstrated for this strain. Coinfection with FD-C and FD-D strains was rare, suggesting possible competition between the two. Similar levels of FDp genetic variation recorded for grapevines or leafhoppers of cultivated and wild areas and co-occurrence of many FDp genotypes inside and outside the vineyards supported the idea of the importance of wild or abandoned Vitis plants and associated S. titanus insects in the epidemiology of the disease. Genetic profiles of FDp found in Clematis were never found in the other hosts, indicating that this species does not take part in the disease cycle in the area. Due to the robustness of analyses using dnaK for discriminating between FD-C and FD-D strains and the high variability of malG sequences, these are efficient markers to study FDp populations and epidemiology at a small geographical scale. IMPORTANCE Flavescence dorée, a threatening disease of grapevine caused by FD phytoplasma (FDp), is distributed within the most important wine-producing areas of Europe and has severe effects on both vineyard productivity and landscape management. FDp is a quarantine pest in Europe, and despite the efforts to contain the pathogen, the disease is still spreading. In this work, new genetic markers for the fine genetic characterization of FDp at local scale are presented. Our findings improve the knowledge of FDp epidemiological cycle and offer the possibility of tracking the route of the FDp infection. In particular, due to its high genetic variability, one of the newly developed markers could be sufficient to track the origin of new infection foci, either from the wild areas or from nurseries.

show abstract

Section: Discussionmentioning

confidence: 88%

Genetic Diversity of Flavescence Dorée Phytoplasmas at the Vineyard Scale

Rossi

Pegoraro

Ripamonti

et al. 2019

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, mathematical modeling of another phytoplasmal grapevine yellows disease, flavescence dorée has been proposed, in which acquisition of the disease, latency and expression of symptoms, recovery rate, removal and replacement of infected plants, and insecticidal treatment have been taken into account (Lessio et al 2015). Flavescence dorée has been also addressed in a space-time point pattern analysis, which highlighted statistics of the disease progression and regression over time (Maggi et al 2017). …”

Section: Introductionmentioning

confidence: 99%

Statistical modeling of long-term grapevine response to ‘Candidatus Phytoplasma solani’ infection in the field

et al. 2017

View full text Add to dashboard Cite

Bois noir (BN) is the most widespread European grapevine yellows disease caused by 'Candidatus Phytoplasma solani'. Although our knowledge of the mechanisms of interactions of this pathogenic bacteria with host is largely unknown, the plant-pathogen system of BN is commonly used as a model system for studying grapevine yellows diseases. We applied here a conceptual model of general plant pathology -a disease triangle for describing interactions among the host plant, the pathogen and the environment. We generated a proofof-concept statistical model for disease triangle using original experimental data and different statistical and data mining approaches for a selected system of 'Ca. P. solani' infection of cv. 'Chardonnay' grapevine plants. We monitored individual plants from a single vineyard over a period of six years. Phytoplasma content, the expression of 21 selected grapevine genes and environmental conditions were recorded and related to disease severity. Our model predicts that in described conditions BN is a function of the expression of grapevine gene VvDMR6, summer rainfall and abundance of 'Ca. P. solani'. The greatest impact among elements of the disease triangle is attributed to the pathogen, and is independent of the pathogen titer. We showed that this first de facto representation of the disease triangle is useful for showing disease dynamics over several years and could be applied to other plant-pathogen systems. The overall results of this study will contribute to understanding of 'Ca. P. solani' biology and its interactions with grapevine host.

show abstract

“…Flavescence dorée, a phytoplasma disease of grapevines, also shows aggregated spatial patterns that are associated with the short‐distance mobility of the vector. Similar to the results here, the spread of flavescence dorée was shown to be predominantly along rows (Maggi et al ., ).…”

Section: Discussionmentioning

confidence: 97%

Spatial patterns of the Citrus leprosis virus and its associated mite vector in systems without intervention

et al. 2018

View full text Add to dashboard Cite

Leprosis is caused by the Citrus leprosis virus cytoplasmic type and is vectored by the mite Brevipalpus yothersi. Miticide applications, which cost $54 million annually, are based on inspection for the presence of mites. The aim of the present study was to characterize the spatial patterns of B. yothersi‐infested trees and trees with leprosis symptoms for further improvement in sampling and disease control. The presence of mites and the occurrence of leprosis were assessed over two years in 1160 Valencia trees and 720 Natal trees in a commercial sweet orange grove in Sao Paulo State, Brazil. To assess the natural growth and dispersal of mites and leprosis, mite populations were not controlled during the experimental period. Maps of mite‐infested trees and trees with leprosis symptoms were analysed at three different levels of spatial hierarchy using complementary methods, i.e. among adjacent trees within and across rows, within quadrats, and the strength and orientation of aggregation among quadrats. The study showed that the spatial patterns of virus‐infected and mite‐infested trees were different, with a strong aggregation pattern of trees with leprosis symptoms that increased over time. Conversely, the spatial pattern of B. yothersi showed randomness or weak aggregation at all three spatial hierarchical levels. Disease incidence increased steadily in plots of both cultivars, unlike in mite‐infested trees where incidence fluctuated over time. These results have important implications for the development of better management strategies for leprosis. Sampling methods and action thresholds for mite control should consider primary disease inoculum in addition to the incidence of mites.

show abstract

Space-Time Point Pattern Analysis of Flavescence Dorée Epidemic in a Grapevine Field: Disease Progression and Recovery

Cited by 24 publications

References 38 publications

Genetic Diversity of Flavescence Dorée Phytoplasmas at the Vineyard Scale

Genetic Diversity of Flavescence Dorée Phytoplasmas at the Vineyard Scale

Statistical modeling of long-term grapevine response to ‘Candidatus Phytoplasma solani’ infection in the field

Spatial patterns of the Citrus leprosis virus and its associated mite vector in systems without intervention

Contact Info

Product

Resources

About